Analysis of Random Neutron Sensor Fluctuations for Surveillance of Nuclear Instrumentation Channels in Nuclear Power Plant Protection Systems

The analysis of the random fluctuations from nuetron sensors operating in the current mode has been shown to be a feasible method for monitoring the dynamic state of neutron measurement channels. A laboratory evaluation of both boron-lined and uranium-lined neutron sensors with simulated sensor and signal cable degradation was completed. The experimental evaluation, supported by a theoretical analysis, has demonstrated the potential for using the power spectral density of the random fluctuations on the detection process as an indicator of change in transient response of a neutron measurement channel.